Brief History of Quantum Cryptography: A Personal Perspective

Quantum cryptography is the only approach to privacy ever proposed that allows two parties (who do not share a long secret key ahead of time) to communicate with provably perfect secrecy under the nose of an eavesdropper endowed with unlimited computational power and whose technology is limited by nothing but the fundamental laws of nature. This essay provides a personal historical perspective on the field. For the sake of liveliness, the style is purposely that of a spontaneous after-dinner speech.Comment: 14 pages, no figure

College of Arts and Sciences summary of research and creative activities, July 1, 1982 to June 30, 1983

Summary of research and creative activities of the College of Arts and Sciences at the University of Central Florida, July 1, 1982 - June 30, 1983

Belleza Desnuda: A Conservation Assessment of the Exterior Concrete Surfaces of Henry Klumb’s Parroquia Nuestra Señora del Carmen in Cataño, Puerto Rico

The Parroquia Nuestra Señora del Carmen was founded in 1893 in the coastal town of Cataño, Puerto Rico. In 1957, the Dominican Catholic Order commissioned architect Henry Klumb to design a modern church, which was inaugurated in June 1962. Since its opening, the Del Carmen Church has remained relatively unchanged, yet efforts to maintain and \u27improve\u27 the building over the years, including painting the original exposed cement stucco exteriors, an important character-defining feature of its design; has contributed toward a misunderstanding and underappreciation of one of Klumb\u27s most significant works on the island. This case study examines Henry Klumb\u27s original design intent for the Del Carmen Church and its subsequent alterations over time, including the current conditions of the concrete and exterior cement stucco in the tropical coastal environment of Puerto Rico. The study was comprised of four phases: Firstly, an in-depth analysis of archival research of the building, its design, the historical context, and its construction and maintenance. The second phases include a conditions survey and assessment with a detailed focus and evaluation of the exterior Portland cement stucco. The third phase focused on physico-chemical analysis of selected samples from the cement stucco and the concrete substrates that included: petrography, micro-drop water absorption testing, microchemical spot test, salt content, carbonation testing, x-ray diffraction (XRD), and scanning electron microscopy with energy dispersive x-ray spectroscopy (SEM-EDS). The last phase recommends a cleaning program to determine the best treatment options for removing the current painted coatings without affecting the cement stucco and aiding the building\u27s restoration to its original appareance. Henry Klumb\u27s Del Carmen Church in Cataño, Puerto Rico, exemplifies how common conservation issues for modern heritage, such as design intent, weathering, authenticity, and material realities, are global concerns and how informed scientific investigations can aid in better interpretation and conservation

The evolution of the cover time

The cover time of a graph is a celebrated example of a parameter that is easy to approximate using a randomized algorithm, but for which no constant factor deterministic polynomial time approximation is known. A breakthrough due to Kahn, Kim, Lovasz and Vu yielded a (log log n)^2 polynomial time approximation. We refine this upper bound, and show that the resulting bound is sharp and explicitly computable in random graphs. Cooper and Frieze showed that the cover time of the largest component of the Erdos-Renyi random graph G(n,c/n) in the supercritical regime with c>1 fixed, is asymptotic to f(c) n \log^2 n, where f(c) tends to 1 as c tends to 1. However, our new bound implies that the cover time for the critical Erdos-Renyi random graph G(n,1/n) has order n, and shows how the cover time evolves from the critical window to the supercritical phase. Our general estimate also yields the order of the cover time for a variety of other concrete graphs, including critical percolation clusters on the Hamming hypercube {0,1}^n, on high-girth expanders, and on tori Z_n^d for fixed large d. For the graphs we consider, our results show that the blanket time, introduced by Winkler and Zuckerman, is within a constant factor of the cover time. Finally, we prove that for any connected graph, adding an edge can increase the cover time by at most a factor of 4.Comment: 14 pages, to appear in CP

What\u27s News At Rhode Island College

https://digitalcommons.ric.edu/whats_news/1046/thumbnail.jp

Reconstructing early modern disaster management in Puerto Rico: development and planning examined through the lens of Hurricanes San Ciriaco (1899), San Felipe (1928) and Santa Clara (1956)

This is the first longitudinal, retrospective, qualitative, descriptive and multi-case study of hurricanes in Puerto Rico, from 1899 to 1956, researching for planning purposes the key lessons from the disaster management changes that happened during the transition of Puerto Rico from a Spanish colony to a Commonwealth of the United States. The selected time period is crucial to grasp the foundations of modern disaster management, development and planning processes. Disasters are potent lenses through which inspect realpolitik in historical and current times, and grasp legacies that persist today, germane planning tasks. Moreover, Puerto Rico is an exemplary case; it has been an experimental laboratory for policies later promoted by the US abroad, and it embodies key common conditions to develop my research interface between urban planning and design, meteorology, hydrology, sociology, political science, culture and social history. After introducing the dissertation, I present a literature review of the emergence of the secular characterization of disasters and a recent paradigm shift for understanding what a disaster is, its causes and how to respond. Next, I summarize the multidisciplinary research and policy knowledge concerning Puerto Rican hurricanes. Subsequently, I explain my methodological sequential data analysis, beginning with three case studies, followed by cross-case comparisons and assessments, ending in answer, recommendations and conclusions. I implemented a version of Grounded Theory, combining deductive and inductive thinking, with a phenomenologist standpoint that valued people's experiences and interpretations of the world. I aimed to denaturalize so-called ‘natural disasters’, exposing with a political economy lens the political character of public decision-making before, during and after a disaster; and grasp how politics impacted the society under study. My research methods were archival research in the field and online, visual sociology and case study. Based on information-oriented sampling, I chose the destructive hurricanes San Ciriaco (1899), San Felipe (1928) and Santa Clara (1956), which occurred at critical historical junctures. I examined three themes: characterization, causation, and relief. Those themes divided into six sub-questions and thirty-eight variables, summarized later. Answer: Disaster management vastly improved mirroring shifting ideas of God, nature, knowledge and humanity; always influenced by the dependent position of the island. Historically, citizens tried to handle hurricanes through mythological beliefs, empirical observations, rituals and material practices; some of which endured colonization and modernization into the mid 20th century. Disaster management emerged haphazardly; at first it was ineffective and improvised relief, without much preventive or reconstructive policy-making. The official perception of hurricanes changed from being essentially uncontrollable religious or natural events, to natural events that could be tamed with technology, physical changes and policies. Yet, it was a more nuanced confluence of environmental, economic, social, cultural, and political factors that enabled storms to become destructive disasters affecting the Puerto Rican economy, environment and society. The social groups that experienced higher resilience or vulnerability during a disaster respectively corresponded to the groups that were best and least served during relief and who could or could not produce public transcripts and policies. Such division resulted from entrenched social and political arrangements, including citizens’ rights, colonial administrative policies, social hierarchy that merged local and external power dynamics, and notions of habitus . Eventually, the growing understanding of citizens’ rights was critical to reduce hurricane casualties and the worst forms of vulnerability through New Deal and Commonwealth developmental projects. By also including contentious aims though, they created other forms of underdevelopment and dependency from the US; whilst technology and modernity paradigms bolstered new risks that would become rather costly. Simultaneously, disaster management became a federal responsibility, which reached Puerto Rico; but it was the unplanned intersection of a hodge-podge of disciplines, approaches and institutions, centered on physical interventions and neglecting the role of culture and the political economy of disasters with negative lasting impacts. Although improvised, contradictory and controversial; the main factors enabling the rise of disaster management were increased governmental leadership, knowledge construction, public awareness, planning and investment in hard and soft infrastructure, and relief provision. My dissertation contributes to Puerto Rican Studies and to emerging planning discussions about the Circum-Caribbean. Also, it contributes to disaster management, an area of academic and practice-oriented literature relevant for planning, fastly growing given the rising frequency and intensity of multiple disasters; and which is usually focused on contemporary events, prospective forecasting and proposal-making. Contrastingly, my dissertation’s strengths reside in being a critical and exhaustive historical study of hurricanes that proposes an option to the customary deleterious disciplinary fragmentation of disaster studies and management, and to the emphasis on physical change that remain standards in most countries

The Trinity Reporter, Spring 2018

Alumni magazine for Trinity College, Hartford, CT.https://digitalrepository.trincoll.edu/reporter/2165/thumbnail.jp

Problems

I. Definition of the Subject and Its Importanc

www.springerreference.com/docs/html/chapterdbid/60497.html Mechanical Computing: The Computational Complexity of Physical Devices

- Mechanism: A machine or part of a machine that performs a particular task computation: the use of a computer for calculation.- Computable: Capable of being worked out by calculation, especially using a computer.- Simulation: Used to denote both the modeling of a physical system by a computer as well as the modeling of the operation of a computer by a mechanical system; the difference will be clear from the context. Definition of the Subject Mechanical devices for computation appear to be largely displaced by the widespread use of microprocessor-based computers that are pervading almost all aspects of our lives. Nevertheless, mechanical devices for computation are of interest for at least three reasons: (a) Historical: The use of mechanical devices for computation is of central importance in the historical study of technologies, with a history dating back thousands of years and with surprising applications even in relatively recent times. (b) Technical & Practical: The use of mechanical devices for computation persists and has not yet been completely displaced by widespread use of microprocessor-based computers. Mechanical computers have found applications in various emerging technologies at the micro-scale that combine mechanical functions with computational and control functions not feasible by purely electronic processing. Mechanical computers also have been demonstrated at the molecular scale, and may also provide unique capabilities at that scale. The physical designs for these modern micro and molecular-scale mechanical computers may be based on the prior designs of the large-scale mechanical computers constructed in the past. (c) Impact of Physical Assumptions on Complexity of Motion Planning, Design, and Simulation: The study of computation done by mechanical devices is also of central importance in providing lower bounds on the computational resources such as time and/or space required to simulate a mechanical syste